/*
 * Copyright (C) 2009, Willow Garage, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the names of Stanford University or Willow Garage, Inc. nor the
 * names of its contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ROSCPP_PUBLISHER_HANDLE_H
#define ROSCPP_PUBLISHER_HANDLE_H

#include <boost/bind.hpp>
#include <boost/thread/mutex.hpp>
#include "ros/common.h"
#include "ros/forwards.h"
#include "ros/message.h"
#include "ros/serialization.h"

namespace ros {
/**
 * \brief Manages an advertisement on a specific topic.
 *
 * A Publisher should always be created through a call to
 * NodeHandle::advertise(), or copied from one that was. Once all copies of a
 * specific Publisher go out of scope, any subscriber status callbacks
 * associated with that handle will stop being called.  Once all Publishers for
 * a given topic go out of scope the topic will be unadvertised.
 */
class ROSCPP_DECL Publisher {
 public:
  Publisher() {}
  Publisher(const Publisher& rhs);
  ~Publisher();
  Publisher& operator=(const Publisher& other) = default;

  /**
   * \brief Publish a message on the topic associated with this Publisher.
   *
   * This version of publish will allow fast intra-process message-passing in
   * the future, so you may not mutate the message after it has been passed in
   * here (since it will be passed directly into a callback function)
   *
   */
  template <typename M>
  void publish(const boost::shared_ptr<M>& message) const {
    using namespace serialization;

    if (!impl_) {
      ROS_ASSERT_MSG(false, "Call to publish() on an invalid Publisher");
      return;
    }

    if (!impl_->isValid()) {
      ROS_ASSERT_MSG(false,
                     "Call to publish() on an invalid Publisher (topic [%s])",
                     impl_->topic_.c_str());
      return;
    }
    if (impl_->md5sum_ == "*" || std::string(mt::md5sum<M>(*message)) == "*" ||
        impl_->md5sum_ == mt::md5sum<M>(*message)) {
      ROS_DEBUG_ONCE(
          "Trying to publish message of type [%s/%s] on a "
          "publisher with type [%s/%s]",
          mt::datatype<M>(*message), mt::md5sum<M>(*message),
          impl_->datatype_.c_str(), impl_->md5sum_.c_str());
    }

    SerializedMessage m;
    m.type_info = &typeid(M);
    m.message = message;

    publish(boost::bind(serializeMessage<M>, boost::ref(*message)), m);
  }

  /**
   * \brief Publish a message on the topic associated with this Publisher.
   */
  template <typename M>
  void publish(const M& message) const {
    using namespace serialization;
    namespace mt = ros::message_traits;

    if (!impl_) {
      ROS_ASSERT_MSG(false, "Call to publish() on an invalid Publisher");
      return;
    }

    if (!impl_->isValid()) {
      ROS_ASSERT_MSG(false,
                     "Call to publish() on an invalid Publisher (topic [%s])",
                     impl_->topic_.c_str());
      return;
    }
    if (impl_->md5sum_ == "*" || std::string(mt::md5sum<M>(message)) == "*" ||
        impl_->md5sum_ == mt::md5sum<M>(message)) {
      ROS_DEBUG_ONCE(
          "Trying to publish message of type [%s/%s] on a "
          "publisher with type [%s/%s]",
          mt::datatype<M>(message), mt::md5sum<M>(message),
          impl_->datatype_.c_str(), impl_->md5sum_.c_str());
    }

    SerializedMessage m;
    publish(boost::bind(serializeMessage<M>, boost::ref(message)), m);
  }

  /**
   * \brief Shutdown the advertisement associated with this Publisher
   *
   * This method usually does not need to be explicitly called, as automatic
   * shutdown happens when all copies of this Publisher go out of scope
   *
   * This method overrides the automatic reference counted unadvertise, and does
   * so immediately. \note Note that if multiple advertisements were made
   * through NodeHandle::advertise(), this will only remove the one associated
   * with this Publisher
   */
  void shutdown();

  /**
   * \brief Returns the topic that this Publisher will publish on.
   */
  std::string getTopic() const;

  /**
   * \brief Returns the number of subscribers that are currently connected to
   * this Publisher
   */
  uint32_t getNumSubscribers() const;

  /**
   * \brief Returns whether or not this topic is latched
   */
  bool isLatched() const;

  operator void*() const {
    return (impl_ && impl_->isValid()) ? (void*)1 : (void*)0;
  }

  bool operator<(const Publisher& rhs) const { return impl_ < rhs.impl_; }

  bool operator==(const Publisher& rhs) const { return impl_ == rhs.impl_; }

  bool operator!=(const Publisher& rhs) const { return impl_ != rhs.impl_; }

  boost::function<void(const SubscriberLinkPtr&)> getLastMessageCallback() {
    return boost::bind(&Impl::pushLastMessage, impl_.get(),
                       boost::placeholders::_1);
  }

 private:
  Publisher(const std::string& topic, const std::string& md5sum,
            const std::string& datatype, bool latch,
            const NodeHandle& node_handle,
            const SubscriberCallbacksPtr& callbacks);

  void publish(const boost::function<SerializedMessage(void)>& serfunc,
               SerializedMessage& m) const;
  void incrementSequence() const;

  class ROSCPP_DECL Impl {
   public:
    Impl();
    ~Impl();

    void unadvertise();
    bool isValid() const;
    void pushLastMessage(const SubscriberLinkPtr& sub_link);

    std::string topic_;
    std::string md5sum_;
    std::string datatype_;
    NodeHandlePtr node_handle_;
    SubscriberCallbacksPtr callbacks_;
    bool unadvertised_;
    bool latch_;
    SerializedMessage last_message_;
    boost::mutex last_message_mutex_;
  };
  typedef boost::shared_ptr<Impl> ImplPtr;
  typedef boost::weak_ptr<Impl> ImplWPtr;

  ImplPtr impl_;

  friend class NodeHandle;
  friend class NodeHandleBackingCollection;
};

typedef std::vector<Publisher> V_Publisher;
}  // namespace ros

#endif  // ROSCPP_PUBLISHER_HANDLE_H
